Bookmark

Quantum Physics

Title:
In defence of naivete: The conceptual status of Lagrangian QFT

Abstract: I analyse the conceptual and mathematical foundations of Lagrangian quantum
field theory (that is, the "naive" quantum field theory used in mainstream
physics, as opposed to algebraic quantum field theory). The objective is to see
whether Lagrangian quantum field theory has a sufficiently firm conceptual and
mathematical basis to be a legitimate object of foundational study, or whether
it is too ill-defined. The analysis covers renormalisation and infinities,
inequivalent representations, and the concept of localised states; the
conclusion is that Lagrangian QFT (at least as described here) is a perfectly
respectable physical theory, albeit somewhat different in certain respects from
most of those studied in foundational work.